The extended X-ray absorption fine structure in the reflectivity at the K edge of Cu

Abstract

The reflectivity of a polycrystalline thin Cu film has been measured around the critical angle of total reflection and around the Cu K edge energy. The relation of the extended X-ray absorption fine structure (EXAFS) to the fine structure observed in the reflectivity above K edge energy is discussed in view of the evaluation of structural parameters of the surface near regions from the reflectivity spectra. The analysis of reflectivity fine structure spectra can be performed by techniques developed for the investigation of EXAFS spectra with additional phaseshift and amplitude functions entering the analysis of the reflectivity spectra. These quantities have been calculated from experiment and agree well with theory. The next-nearest Cu-Cu bond length in the surface region of Cu has been found to agree with the bulk value to within 0.01 AA.